AuzenTech has delivered some impressive sound cards using audio chips from the likes of C-Media, but now it's taken a huge leap forward with a Creative X-Fi chip.

For many years there has been a distinct separation between sound cards. There are Creative cards which use Creative chips (Live!, SoundBlaster, Audigy and X-Fi) and there are the rest. A Creative sound card has two significant advantages over the competition. One is the support from games developers, as Creative has a long history, while the likes of Hercules, M-Audio, Philips and Videologic come and go from the sound card market.

The other major advantage that Creative offers to games developers is EAX or Environmental Audio eXtensions. EAX offers surround sound effects and audio cues that are to gaming what Dolby is to the movies. Gamers want to hear the bad guy walking down the stone corridor so they can judge the moment when they will appear in an open doorway, and everyone needs a hint when they're about to be attacked from behind by a monster.

Creative made EAX 2.0 an open standard that is an extension of Microsoft's DirectSound3D, which was a part of DirectX up to Windows XP. Creative kept versions 3.0, 4.0 and 5.0 of EAX as proprietary technology so you can play any game with any decent sound card and be sure that you'll get a certain standard of audio support, but when you plug in an X-Fi the ambient audio takes a leap forward.

AuzenTech was able to deliver a superb sound card in the X-Meridian 7.1 thanks to the CMedia CMI-8788 chip, but the EAX support was unimpressive so it didn't especially appeal to gamers. The only way forward was a move to Creative chips. Enter, stage left, the AuzenTech Prelude X-Fi which is, to all intents and purposes, a Creative X-Fi Xtreme Gamer Fatal1ty Pro.

Make no mistake, this isn't a Creative sound card with an AuzenTech badge, as it is most definitely manufactured by AuzenTech and the components seem to have a slightly higher quality than those used by Creative. The Fatal1ty X-Fi has a signal-to-noise ratio of 109dB and the X-Fi Elite Pro, which is an external unit, has a s/n ratio of 116dB, but the Auzentech eclipses that with a figure of 120dB.

The problem is that we mere mortals cannot hear the difference between a Creative X-Fi and the AuzenTech Prelude. It's a similar story with another innovative feature that is offered by AuzenTech, as you can pop out the OPAMP chips on the front stereo channels and replace them as a ‘convenient do-it-yourself upgrade for ultimate analogue sound quality and colour.'

I can think of no situation when I would buy and install chips on a sound card, but just in case I do AuzenTech sells them for US$49.99 or $59.99 depending on the model of chip.

The quality of the hardware isn't in doubt and the array of analogue mini jacks is backed up by a pair of coaxial S/PDIF digital ports. Plug in the supplied optical adapters and the single optical cable and you have a decent choice of connections, but AuzenTech sells the customer slightly short as it keeps the X-Tension DIN add-on as an extra that costs $59.99. You're paying top dollar for the Prelude X-Fi and it's reasonable to assume you're getting something special, when instead the sound card is little more than a posh X-Fi.

The other problem is the drivers. Creative has been castigated about its drivers for years, although it got them pretty much right for the Audigy, and they have stayed right for X-Fi. The problem is that Microsoft ripped DirectSound3D out of DirectX 10 and in the process it broke EAX quite comprehensively.

The result is that Creative had to devise some software called Alchemy to restore the ambient audio features, so most of the driver development for the X-Fi chip has been spent making Vista work as well as Windows XP. The first drivers for the Prelude X-Fi were quite blatantly nothing more than Creative drivers with an AuzenTech logo. The current driver version is RC5-1 so even now they are still tagged as a Release Candidate, which hardly inspires confidence.

You're paying a high price for the Prelude X-Fi and, while it is undoubtedly a fine sound card, it seems as though the DirectX changes in Windows Vista have left it as a work in progress. No doubt it will be superb when it is finished, but that may take a while yet.